Gun violence is one of the major public issues for a sustainable society. In the United States, the number of suicide deaths by gun is larger than that of homicide by gun. More than 60 percent of gun deaths are suicides. Accidental use of gun by children is also a significant concern. Minimization of these problems is therefore desirable. To date, no system has proven to be entirely satisfactory. Therefore, an improved system is desirable that addresses at least some of these concerns.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.